Spherical displacement device and seal means therefor

ABSTRACT

The present invention relates to a positive displacement spherical device comprising a housing having a generally spherical cavity of chamber therein with a diametrically extending piston positioned between a pair of rotating wedgeshaped pistons which have their axes disposed at an angle with respect to each other so that rotation of the wedge-shaped pistons causes the central diametrically disposed piston to simultaneously rotate and oscillate to thus positively displace fluids between the adjacent surfaces of the central piston and the end pistons. The present invention also includes seal means for sealing piston to piston and piston to housing in such spherical displacement device to prevent leakage from the high pressure to the low pressure chambers formed between the pistons in the housing. Such spherical displacement device can be used either as a pump, compressor or gas expander and, with the addition of suitable ignition apparatus, as an internal combustion engine.

[ June 11, 1974 SPHERICAL DISPLACEMENT DEVICE AND SEAL MEANS THEREFOR [75] Inventor: Samuel M. Berry, Dallas, Tex.

[73] Assignee: Commercial Metals Company, Dallas, Tex.

[22] Filed: Dec. 26, 1972 [21] Appl. No.: 318,259

Related US. Application Data [63] Continuation-impart of Ser. No. 110,928, .Ian. 29,

1971, abandoned.

[52] US. Cl 418/68, 418/112, 418/143, 277/160 [51] Int. Cl...... F0lc 3/00, F0lc 19/00, F04c 27/00 [581 Field of Search 418/68, 104, 112, 116, 418/142, 143; 277/160, 161

[56] References Cited UNITED STATES PATENTS 389,927 9/1888 Hurdle et a1 418/68 1,409,986 3/1922 White 418/112 2,128,372 8/1938 Marien... 277/161 2,621,852 12/1952 Pisa 418/68 3,083,699 4/1964 Froede... 418/116 3,156,221 11/1964 Miller 418/68 3,357,412 12/1967 Sabet 418/142 3,664,778 5/1972 Nilsson 418/142 Primary Examiner-Carlton R. Croyle Assistant Examiner.lohn .1. Vrablik Attorney, Agent, or FirmPravel, Wilson & Matthews [5 7] ABSTRACT The present invention relates to a positive displacement spherical device comprising a housing having a generally spherical cavity of chamber therein with a diametrically extending piston positioned between a pair of rotating wedge-shaped pistons which have their axes disposed at an angle with respect to each other so that rotation of the wedge-shaped pistons causes the central diametrically disposed piston to simultaneously rotate and oscillate to thus positively displace fluids between the adjacent surfaces of the central piston and the end pistons. The present invention also includes seal means for sealing piston to piston and piston to housing in such spherical displacement device to prevent leakage from the high pressure to the low pressure chambers formed between the pistons in the housing. Such spherical displacement device can be used either as a pump, compressor or gas expander and, with the addition of suitable ignition apparatus, as an internal combustion engine.

12 Claims, 22 Drawing Figures slelelosa PATENTE-mun 1 1 m4 sum u or a PATENTE'DJum 1 I974 SHEEI' 8 0F 8 SPHERICAL DISPLACEMENT DEVICE AND SEAL MEANS THEREFOR CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of application Ser. No. 110,928, filed Jan. 29, 1971 and now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention pertains to a spherical displacement device and means for sealing between the moving parts thereof. The term spherical displacement device shall, for the purpose of this patent application, mean a device having a chamber'therein which is at least partially spherical and having one or two wedge-shaped spherical sections or pistons with faces converging at the center of the spherical housing with a disc-shaped center piston extending diametrically of said spherical housing and adapted to rotate with said wedge-shaped end piston and to also oscillate with respect thereto. Suitable inlet and discharge passages are provided in the housing so as to draw in and discharge the volume displaced on each revolution of the pistons. In some embodiments, one of the wedge-shaped end pistons is fixed against rotation and the other is mounted on a rotatable crank which is inclined toward the center of the sphere butoffset with respect to the axis of rotation of such crank so as to cause the crank to describe a cone as it rotates. With this configuration, the center piston is caused to oscillate between the fixed rear piston and the rotating first piston.

2. Description of the Prior Art There have been various attempts in the past to provide spherical power devices which overcome the inherent inertial disadvantages of reciprocating devices. Such spherical displacement devices typically employ one or more wedge-shaped pistons which are mounted for rotation in a spherical housing on opposite sides of a central piston which rotates with and oscillates between the wedge-shaped end pistons to provide an improved pump, compressor or engine. In these prior art devices, which are typified by the U.S. Pat. to Froude, Nos. 295,380 and 312,116, as well as in the U.S. Pat. to Hurdle et al, No. 389,927, the end pistons are mounted for rotation about axes which converge at the center of the spherical housing. These old patents show the three-piston arrangement employed in spherical power devices and disclose various means for sealing the pistons with respect to each other and with respect to the surrounding spherical housing. However, each of these devices is burdened with the inherent shortcomings of the various sealing means employed for sealing between the respective pistons and between the pistons and surrounding housing. While some of the seals disclosed in these patents may be suitable for use at low pressures, they are unsuitable for use in high pressure devices, such as freon compressors, inasmuch as they allow the high pressure fluid to leak from behind the seals or along the seals and thus escape from the high pressure to the low pressure chamber and thereby render the devices inefficient or ineffective for use as high pressure compressors. Various other spherical power devices have been proposed, however, many of them do not even attempt to provide seal means for sealing between the various pistons and the surrounding spherical housing.

While the prior art patents have generally placed their sealing rings in obvious locations, such as around the central and outer pistons and across the central piston journals, they have failed to provide a leak-tight seal system which will seal all leak paths in each individual chamber. This in a result of not providing a seal system which adjusts to the variation of clearance between the internal rotating members and the inside spherical bore of the housing, i e., variations in clearance due to imperfections in manufacturing and deflections of the rotating parts due to heat and loads. Further, the prior art sealing systems have not sealed effectively at all joints; that is, to be effective in high pressure systems, there must be provision for compensating for wear so as to maintain a positive seal at each seal joint regardless of which of the individual seals wears. Also, provision must be made to prevent high pressure working fluid from leaking along a path down the face of the seal and under its inside radius to the low pressure side.

SUMMARY OF THE INVENTION The present invention comprises a sealing system for sealing all leak paths found in a spherical displacement device which comprises a housing having a generally spherical chamber therein with a central piston extending diametrically of the chamber and with semicylindrical journals extending diametrically across opposite sides or faces of the central piston and disposed at substantially right angles relative to each other. End pistons which are wedge-shaped spherical sections are disposed on opposite sides of the central piston at an angle other than with respect to each other and have diametrically extending semi-cylindrical grooves therein for receiving the respective journals formed on the opposite sides of the central piston. The sealing system with the present invention includes a plurality of circumferentially extending ring seal segments which are provided on the spherical shaped portion of the end pistons for sealing between them and the spherical housing as well as circumferentially extending ring seal segments which are positioned on the outer edge of the central disc piston for sealing between it and the outer spherical housing. Further, pin end seals are provided on the ends of the journals which connect the center and end pistons. With this sealing arrangement, plug seals are also provided with the circumferentially extending ring seal segments to prevent high pressure leaks along or behind the ring seal segments. Further, wedge-shaped seal members are provided for sealing between the pin end seals on the journals and the side seals on the spherical section end pistons. With this arrangement, a sealing system is provided which employs only metal or other rigid parts for sealing to thus provide a means for sealing against the loss of relatively high pressure.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial side view showing the internal pistons of a spherical displacement device including two end pistons on opposite sides of a central disc-shaped piston arranged for rotation in the spherical chamber;

FIG. 2 is a sectional view taken on line 22 of FIG. 1 showing the seals on the end pistons;

FIG. 3 is a sectional view taken on line 33 of FIG. 1 showing further details of the seals on the disc-shaped central piston;

FIG. 4 is a partial side view of the spherical displacement device showing the details of an alternate piston seal arrangement;

FIG. 5 is a sectional view taken on line 5-5 of FIG. 4 showing the ring seal means on the end piston;

FIG. 6 is a sectional view taken on line 6-6 of FIG. 4 showing additional details of the seals on the end piston;

FIG. 7 is an exploded view of the plug seal;

FIG. 8 is a side view of the disc-shaped center piston with plug seals in association with the ring segment seals;

FIG. 9 is a sectional view taken on line 9-9 of FIG. 8 showing additional details of the plug seals;

FIG. 10 is a side view of an alternate embodiment of the seal ring on the end piston;

FIG. 11 is a sectional view taken on FIG. 10;

FIG. 12 is a sectional view taken on line 12l2 of FIG. 10 showing additional details of the sealing arrangement for the end pistons;

FIG. 13 is a side view of another alternate embodiment of the sealing arrangement for an end piston;

FIG. 13A is a side view of an alternate embodiment of an end piston with the circumferentially extending ring disposed at an angle with respect to the axis of rotation of the piston;

FIG. 14 is a sectional view taken on line 14-14 of FIG. 13 showing other details of this alternate sealing arrangement;

FIG. 15 is a sectional view of the compressor embodiment of the spherical power device of the present invention including means for sealing the various pistons with respect to ths spherical housing;

FIG. 16 is a rear elevation taken on line l616 of line 11-11 of FIG; 16 showing inlet ports in the compressor housing;

FIG. 17 is a sectional view taken on line 17--17 of FIG. 16 showing additional discharge valve details;

FIG. 18 is a partial sectional view taken on line 18-18 of FIG. 15 showing the inlet and discharge passages in the compressor housing;

FIG. 19 is a sectional view taken on line 19-19 of FIG. 18 showing additional details of the inlet and discharge passages in such housing.

FIG. 20 is a schematic view showing an alternate embodiment of the spherical displacement device wherein one end piston is fixed and the other is mounted for rotation so as to cause the center piston to oscillate between the fixed and rotatable end pistons.

FIG. 21 is an isometric view of the embodiment shown in FIG. 20.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 1 of the drawings, the apparatus of the present invention comprises a housing I-I having a spherical chamber or cavity C formed therein for receiving the pair of end pistons P-1 and P-2 which are rotatably mounted in the housing H with the axis P-l' of the piston P-l aligned at an angle with respect to the axis P-2' of the piston P-2 with such axes converging at the center C of the spherical chamber C. Between such facing pistons P-1 and P-2 is mounted the central or intermediate piston P-3 which rotates with the end pistons and simultaneously oscillates between such pistons as it rotates with them.

The piston P-l comprises a substantially hemispherical body 3 having a pair of inwardly inclined faces or surfaces 5 and 6 which are connected by their inner edges 5a and 6a by longitudinally extending concave groove or channel 9 that extends diametrically across the piston P-l. As shown, the piston shaft 14 on which the piston is rotatably mounted in the housing H, is positioned on the axis P-l which extends at essentially a right angle to the groove 9. The piston P-2, also shown in FIG. 1 of the drawings, is substantially identical to the piston P-! in that it also has a substantially hemispherical body 4 and is provided with inclined faces 7, only one of which is shown in FIG. 1. Such piston P-2 is provided with a diametrically extending groove which is substantially perpendicular to the axis P-2' on which the piston P-2 rotates.

The central or center piston P-3 comprises a circular plate or disc-shaped member 10 which also includes substantially plane and parallel opposite sides 11 and 12, respectively. Each side is divided into sections by means of the diametrically extending journal means 15 and 16 which extend across the surface of the plane sides 10 and 11. Such journals 15 and 16 are provided with a convex curved semi-cylindrical outer surface which is substantially the same radius as the groove 9 in the piston P-l in which such journal 15 is normally received. Such journals l5 and 16 are disposed at substantially right angles with respect to each other and are on opposite sides of the disc-shaped member 10. Also, the outer circumferentially extending edge of the disc-shaped member 10 is curved at substantially the same radius as the inner surface of the spherical chamber or cavity C in the housing H.

The seals shown in FIG. 1 of the drawings include the pin end seal members 20 and 21, respectively, which are generally semi-cylindrical so as to conform to the outer surface of the journal members 15 and 16. The center piston is also provided with center ring seals 22 and 24 which extend circumferentially around the outer perimeter of the center disc-shaped piston. Such rings 22 and 24 are disposed in suitable grooves in the curved edge of the center piston and are positioned with their ends abutting the pin end seals 20 and 21, respectively.

FIG. 3 shows additional details of the sealing arrangement for the center piston P-3 including the wedgeshaped end seal members 30 which engage the tapered ends 31 of the ring segment seals 22 and 24. Also shown is the'spring member 33 which is positioned in the ring groove in the center piston for urging such ring segment seals 22 and 24 radially outwardly into engagement with the inner surface of the spherical chamber C. As shown in FIG. 3 of the drawings, when the piston P-3 is rotated in a counterclockwise direction as indicated by the arrow 35, the frictional force on the outer ring segment seals 22 urges such ring segment in a clockwise direction as indicated by the arrow 36. The frictional force on such ring segments tends to cause the ring 22 to resist rotation with the piston P-3 so that the trailing end 220 of the ring 22 is jammed against the wedge-shaped seals 30 and the adjacent pin end seals 20 in the side following rotation. This reaction along with the extending of the seals creates a clearance in the seal joint adjacent the ends 22b leading rotation which would provide a leak path unless compensated for by the wedge-shaped seals 30 adjacent the leading ends 22a of the rings 22. As shown in the drawings, such wedge-shaped seals are urged outwardly into sealing engagement between the tapered ends of the rings 22 in the adjacent surface of the pin end seal 20 by means of the ends of the springs 33.

The pin end seals 20 and 21, provided at the opposite ends of the diametrically extending journals and 16 on the center piston, are positioned in grooves 38 which extend further into the center piston body than the grooves such as 220 in which the outer seal rings 22 and 24 are positioned in order to prevent high pressure fluid from leaking under such outer rings, around the ring groove and under the opposite ring on the low pressure side. In other words, the pin end seals close the ends of the ring grooves such as 22c to prevent high pressure fluid from leaking from one groove to another. Also, to prevent fluid from passing between the pin end seals and 21 and the adjacent journal surface 15a as shown in FIG. 1, the radius of the journal 15 and the radius of the adjacent side of the pin end seal 20 are substantially the same. To provide a satisfactory seal, the pin end seal 20 must also seal at its opposite ends 20a and 20b. In order to accomplish this without making the parts extremely precise and expensive to manufacture, the pin end seal 20 is manufactured with a smaller arc length than the corresponding arc length of the journal 15 so as to permit the pin end seal 20 to slide around the journal some slight amount as a result of friction of the outer pistons as the center piston moves relative to the outer piston on the compression stroke. This friction causes one end of the pin end seal 20a or 20b, whichever is applicable, to contact the adjacent center piston face which in turn prevents the high pressure fluid under the outer center ring from leaking to the outside between the pin end seal and the center piston at either end of such pin end seal. Also, it should be noted that the outer edges such as 21a of the pin end seals are beveled or curved at their outer edge so as to conform to the spherical configuration of the ends 15a of the journal 15 and to fit the radius of the spherical chamber C.

Considering next the seals on the outer piston P-l as shown in FIGS. 1 and 2 of the drawings, the outer seal rings 12 which are positioned in ring grooves 13 in the piston P-l are forced outwardly against the inner spherical surface of the surrounding housing H by means of springs 40 as well as the fluid pressure which will leak under such outer piston seal rings. The seals 12 are free to adjust to variations in clearance between the spherical housing and the spherical rotor due to deflection, load or heat. The ends of the outer piston rings 12 are tapered at 12a so as to receive the seal wedges 41 which are carried in grooves aligned with the grooves of the outer ring seal 12 and which are provided with suitable springs 48 for urging the wedge-shaped seals outwardly into engagement with the tapered ends of the seals 12. Such seal wedges or locks are free to move longitudinally of the journals, such as 15, so as to fill the gap at the ends of the ring seals 12. Thus, when the frictional forces imposed upon the seal 12 cause it to move relative to the piston P-l, the wedge-shaped member will tend to fill the gap and thereby prevent a leak path at the end of such ring seal. Also, the seals 41 overlap the pin end seal 20 so as to seal between the ends of the ring seal 12 and the adjacent pin end seal.

Suitable spring means such as that illustrated at 48 may be used to urge the wedge-shaped seal members 41 longitudinally of the journal and into sealing engagement with the ends of the arcuate ring seal segments 12.

Cross seals 46 are also provided for sealing between the journal 15 and the corresponding curved portion of the end piston P-l adjacent thereto. Such cross seals 46 seal the base of the pin end seals 20 and 21, and as shown in the drawings, the cross seals are preferably provided with a lap joint 47 to permit longitudinal movement of the seals relative to the journal to compensate for pin end seal wear. Such lap joint normally comprises overlapping end segments of the seal members which are approximately one-half of the normal thickness of the cross seal. Such overlapping construction is provided to accommodate longitudinal movement between the various seal strips or pieces in the cross seal.

It will be appreciated that the outer piston seals referred to hereinabove must combine with the center piston seals to make a total system in which each chamber is sealed from the other chambers in the spherical displacement device.

As shown in FIG. 1, the seals 12 are disposed in grooves 13 which are aligned substantially parallel to the planes of the faces 5 and 6, respectively, of the piston P-l. An alternate embodiment of the sealing system of the present invention is shown in FIGS. 4, 5 and 6 of the drawings wherein the center piston seals are identical to those previously described with respect to the FIG. 1 embodiment but the seals for sealing the outer piston P-l are arranged to provide a circumferentially extending seal that is disposed in a plane substantially perpendicular to the axis of rotation P-l' of the piston P-l. As shown in FIG. 4 of the drawings, the seal 50 is disposed in a groove 51 that is perpendicular to the axis of rotation of the piston P1 with a side seal 52 disposed in a plane, substantially perpendicular to the plane of the seal 50. The side seal 52 provides a means for sealing the ends of the ring segments 50 and also provides a means for sealing between the piston P-1 and the pin end seal 20 on the journal 15.

As shown in FIG. 6 of the drawings, the cross seals 52 cover the ends of the ring seal segments 50 and the groove 51 in which such ring seal segments are disposed. Such cross seals 52 are provided with a curved outer surface 52a which is shaped to conform to the inner surface of the spherical chamber and are provided with a tapered end portion 54 which is tapered or inclined to receive the wedge members 55 which are provided between the side seals 52 and the adjacent pin end seal 20. As shown in FIG. 6 of the drawings, the wedge members 55 are provided with spring means 57 which urge the wedge outwardly so as to fill the space between the tapered surface of the side seal 52 and the adjacent surface of the pin end seal 20. Also, as shown in FIG. 6 of the drawings, an inner cross seal 60 is shown for sealing between the center piston journal member 15 and the piston P-l. Also, as shown in the drawings, the wedge-shaped seals 55 overlap the juncture between the end of the cross seal 60 and the inner end of the pin end seal 20.

FIG. 5 shows the circumferentially extending seal 50 which comprises segments 50a and 50b which are disposed in the groove 51 in the piston P-l. Spring means 60 are provided in the groove 51 beneath the segments 50a and 50b for urging them radially outwardly into engagement with the inner surface of the surrounding spherical housing. The side seals 52 are shown on opposite sides of the piston P-I with suitable wedge seal members 62 provided adjacent the tapered ends of the ring segments 50a and 5012, respectively, and positioned between such tapered ends and the adjacent side of the side seals 52.

Also as shown in FIG. of the drawings, the opposite end of the ring segments from the tapered end is provided with a radially extending surface 64 for engaging the adjacent side of the side seal 52. The outer ring seal segments 50a and 50b are free to float and compensate for wear or misalignment between the inner pistons and the outer spherical housing. As shown, rotation of the end piston P-l clockwise as indicated by the arrow 65 will create frictional forces in a counterclockwise direction as indicated by the arrow 66 which will tend to move the ring seal segments 50a and 50b in a counterclockwise direction thereby forcing the ends 64 of the ring seal segments into sealing engagement with the adjacent side seal 52 and also opening or spreading apart the opposite tapered ends of the ring seal segments from the opposite sides of such side seals 52. The wedge-shaped seal members 62 adjacent the tapered ends will move radially outwardly to close any gap between such tapered ends of the seal segments 50a or 50b and the sides of the side seal 52 adjacent thereto. Further, it will be appreciated that in the FIG. 4 embodiment the side seal members 52 engaging the ends 64 drive such segments with the piston P-1 and cause them to rotate with the pistons. Such side seals also prevent high pressure fluid from leaking from under the outer ring seals from the high pressure side to the low pressure chamber be being recessed deeper into the piston than the outer seal ring groove 51 as best seen in FIG. 5 of the drawings. It will also be appreciated that the seal 50 may be formed of a single piece rather than of a plurality of segments in which case, one of the side seals 52 will be relieved or notched so as to enable the one-piece seal to pass therethrough. Such single piece seal will have one end such as the end 64 which engages one side of a side seal and another end tapered as illustrated in FIG. 5 of the drawings with a suitable wedge-shaped seal disposed between the tapered end and the adjacent side of the side seal member.

FIGS. 7, 8 and 9 show details of another preferred embodiment of the apparatus of the present invention which includes a plurality of plug seals used in conjunction with the various ring seal segments for sealing the spherical displacement device. As shown in the drawings, circular rings or ring seal segments 70 extend around a circumference of the central piston P-3 in suitable grooves 72 formed in the outer edge thereof. As shown a lap joint 74 is provided at the ends of the ring 70 to facilitate placing the ring on the central piston and helps prevent high pressure gas from leaking from under ring and when made as shown the edge trailing rotation holds down the leading edge of the ring and prevents it from hanging ports or other openings in the housing surface. A pin is provided for locking the ring in the groove to thereby prevent from rotating relative to'the piston.

Plug seals are provided for sealing each ring seal 70 at its juncture with the opposite ends of the pin end seal 20. The plug seals 80, which are shown in an exploded view in FIG. 7, are disposed in suitable cylindrical openings 82 formed in the center piston or the end pistons, at the case may be. Such plug seals comprise a tubular body 80 having an opening 80b extending therethrough and having a notch 88 in the outer end for receiving the ring seal 70. Such plugs are additionally provided with a slip fit in the openings 82 and are preferably provided with springs 85 for urging the plugs outwardly into engagement with the surrounding seal ring 70. As shown in the FIG. 7 embodiment, the plug seals 80 comprise a tubular member having a passage or opening 80b extending therethrough for receiving a sliding piston 800 which is urged outwardly by means of fluid pressure which is introduced into the cylindrical opening 82 in a manner which will be described in detail hereinafter. The piston 80c is designed to have a sliding fit in the passage 80b so that it can be urged outwardly so as to engage the inner surface 70a of the ring 70. The outer end of the plug 80c is curved to conform to the inner surface or radius of the seal ring 70 and the outer end of the tube 80a is curved so as to conform to the radius of the spherical chamber in which the center piston rotates. The depth of the notch 88 inwardly of the tubular member 80 need not be held to close tolerance since the sliding piston 80c will move outwardly into engagement with the inner surface of the ring 70 to form a seal therewith and thus compensate for any difference between the depth of the notch and the thickness of the seal ring 70. Thus, by using two pieces (the tubular member 80a and the piston 80c) the number of critical dimensions which must be held in manufacturing is reduced. However, it will be appreciated that a solid plug may be provided with a notched end for sealing the outer seal ring in the central piston.

FIG. 10 shows an alternate embodiment of the seal system of the present invention wherein a circumferentially extending ring seal 90 is provided in a suitable groove 91 formed on the piston P-l with the seal 91 aligned substantially perpendicular to the axis of rotation P-l of the piston P-l. The side seal 92 is disposed substantially perpendicular to the circumferentially extending seal 90 and is disposed in the suitable groove 93in the body of the piston P-l. A plug seal 95 is provided at the juncture of the side seal 92 and the ring seal 90 as shown in FIGS. 10 and ll of the drawings. Such side seal 92 is substantially the same as the side seal 52 shown in FIG. 6. Such side seal 92 has a tapered forward edge which is inclined to receive the wedgeshaped seal member 96 which is similar to the wedgeshaped seal 55 shown in FIG. 6. The plug seal 95 is slidably mounted in the cylindrical opening 82 formed in the piston P-l. The seal 82 has a notch at its upper end for receiving the seal ring 90 and a spring 97 is provided in the lower end of the cylindrical opening for urging the plug 95 outwardly. Also, as shown in FIG. 11 of the drawings, a passage 99 communicated fluid pressure produced by operation of the spherical power device to the chamber or opening 82 for urging the plug 95 radially outwardly into sealing engagement with the seal ring 90. The passage 99 is connected to the groove 100 in which the spring 101 and cross seal 102 are normally positioned. Thus, in the event high pressure fluid leaks behind the cross seal member it will be communicated to the cylindrical opening 82 behind the plug seal 95 and such high pressure fluid will then be used to urge the plug outwardly and assist in sealing the piston P-l with respect to the surrounding spherical housing.

Also, as shown in FIG. 11 of the drawings, the outer end of the plug seals 95 are provided with a curved surface 95a which corresponds to the radius of the spherical chamber in the housing I-I. Further, the seal ring 90 is also provided with a curved surface 90a that also conforms to the radius of such spherical chamber.

FIG. 12 is similar to FIG. 9 in that it shows the plug seal 95 in conjunction with the ring seal 90, however, the FIG. 12 embodiment has only a pair of plug seals 95 as there is only a single plug seal on each side of the end piston P-1.

As shown in FIG. 13A of the drawings, there is another alternate embodiment of the seal means of the present invention which includes a circumferentially extending seal member 110 which is disposed in a groove 111, wherein the groove 111 is inclined at an angle with respect to the axis P-1' of the piston P-l so as to be a few degrees out of perpendicular with that axis. With this arrangement, it will be appreciated that the circumferentially extending seal 110 will be caused to wobble with respect to the axis of rotation P-l' as the piston P-1 is rotated so to thereby interject some lateral movement or sweep in the course of the rotating seal 110 with respect to the inner surface of the spherical housing. Such sweeping motion will facilitate the lubrication of the piston seal 110 as well as the area of the spherical housing which is swept by the wobbling rotation of the seal in the housing.

FIGS. 13 and 14 show another alternate view of a sealing system for sealing between the piston P-1 and the surrounding spherical housing wherein a circumferentially extending ring seal 110 is disposed in a groove 111 which is substantially perpendicular to the axis of rotation P-l of the piston P-l. As shown, a pair of side seals 112 and 113 are provided on the piston P-l, which side seals are substantially the same as the side seals shown in FIGS. and 11 with the exception of the alignment and location of such side seals with respect to the circumferentially extending seal 110. As shown in FIG. 13, the side seals 112 and 113 are disposed at an angle other than 90 with respect to the circumferentially extending seal 110 and are provided with plug seals 114 and 115, respectively, which seal the juncture between such side seals and the circumferentially extending seal. The plug seals 114 and 115 are also substantially the same as the plug seals 95 shown in FIGS. 10 and 11. With the FIG. 13 embodiment, there are thus provided two side seals 112 and 113 for sealing between the piston P-1 and the pin end seal 20 on the journal 15 and also for sealing the piston P-l with respect to the outer surrounding housing H. As shown in FIG. 14, the circumferentially extending seal 110 is provided with a lap joint 120 and, if desired, a pin 121 may be provided for locking the seal 110 in the groove 111 to thereby assure rotation of the seal 110 with the piston P-l.

Further, it will be understood that with each of the embodiments illustrating the various sealing systems of the present invention, such seals have been described with respect to the journal 15 on one side of the center piston P-3 and also with respect to the piston P-l. However, it will be understood that the sealing systems described may also beused on the opposite side of the center piston P-3 for sealing with respect to the journal 16 and also the piston seals may be used for sealing the piston P-2.

Considering now the compressor embodiment of the spherical displacement device shown in FIGS. 15-19 of the drawings, the housing designated generally H in FIG. 15 comprises two end sections 200 and 201 with spherical chamber portions C therein, which house the pistons P-1, P-2 and P-3. In this embodiment of the invention, the housing H is surrounded by a cylindrical body or case 205 which has a circular rear end plate 205a which is welded or formed integrally with the case 205. The case 205 is sealed with the front end section 200 by means of an O-ring 206 or other suitable sealing means. Also, an intermediate seal is formed by an O- ring or other suitable seal 210a which extends circumferentially between the exterior housing section 200 and the interior surface of the body or case 205 to provide a pair of sealed passages or manifolds 208 and 210 which serve as fluid inlet conduits and fluid discharge conduits, respectively.

The housing section 200 is provided with a neck 214 having a bore 215 therein for receiving suitable bearings 216 for mounting the shaft 218 of the piston P-l. The shaft is shown with a pully 219 keyed thereto for driving the piston P-l. Bearings 220 are mounted in the housing 200 for engaging a bearing race 221 formed at the outer edge of the piston skirt 223.

Similarly, the piston P-2 is provided with a shaft 225 that is mounted in suitable bearings 226 carried in a bore 228 in the housing portion 201. Also, bearings 229 engage the bearing race 231 on the rear surface of the piston skirt 233 of the piston P-2.

As shown in FIG. 15 of the drawings, an inlet passage 235 is provided in the housing 201 for connecting a suitable fluid inlet line thereto. A one-way check valve 236 is provided at the passage 235 to prevent back flow through such inlet. In the preferred form of this invention, the check valve comprises a reed type check valve which includes a reed 237 and a reed stop 239. The valve 236 opens only when there is a lower pressure in the manifold 208 than in the inlet passage 235.

FIGS. 18 and 19 show the interior inlet passage 240 which communicates incoming gas, such as freon or the like, from the inlet manifold 208 to the spherical chamber C in which the pistons P-l, P-2 and P-3 are working. The passage 240 is formed in the housing section 200 and has a pair of spaced ports 241 and 242 for communicating opposite sides of the central piston P-3.

of the drawings for limiting the travel of the reeds 255.

With this arrangement, compressed fluid such as freon discharged through the ports 250 and 251 into the discharge passage 210 is not allowed to back up into the spherical power device and a suitable discharge port 257 is provided in the cylindrical case 205 for connecting a tube or other conduit thereto.

As shown in FIG. 15 of the drawings, the piston P-l is provided with arcuate ring-type seals 270 and 271, which are positioned in suitable grooves 272 and 273 formed in the piston body adjacent the surfaces and 6. Such seals engage the spherical inner surface of the chamber C as such piston rotates about its axis.

Similarly, bar or strip seals 277 and 278 are provided in suitable grooves 279 and 280, respectively, which are formed adjacent the longitudinally extending semicylindrical groove which receives the split journal 15.

Transversely extending seals 283 are provided in suitable slots or grooves shown adjacent the opposite ends of the split journal 16 for sealing it with respect to the adjacent piston. Also, the seal 283 seals the end of the journal 16 and the adjacent interior surface of the spherical chamber C, and also seals the ends of the cross seals 277 and 278. Similar grooves and seals are provided also adjacent the opposite ends of the split journal 15. Similarly, suitable grooves and seals such as those shown in the piston P-l are also provided in the piston P-2 for sealing it with respect to the spherical chamber C and also with respect to the journal 16.

A pair of ring seals 285 and 286 are shown extending circumferentially of the central body portion of the center piston P-3. Such seals are positioned in suitable grooves 287 formed in such plate 25. Thus, it will be appreciated that with the various seals provided in the pistons P-1 and P-2 as well as in the piston P-3, the compressor apparatus shown in FIG. may be operated at pressures substantially in excess of atmospheric pressure.

The compressor shown in FIG. 15 is also provided with an oil pump 290 shown secured to the shaft portion 225 of the rotatable piston P-2. The oil pump 290 pumps oil through a central passage or bore 300 extending longitudinally of the shaft 225 into suitable oil conduits 301 for depositing oil on the curved surfaces of the split journal 16 and the adjacent surface of the piston. Other oil passages 303 are provided for conducting oil to the bearings 229.

A passage 304 extends through the center of the plate 25 and also through the journal 15 for conducting lubricating oil to the longitudinally extending groove 308 in the piston P-l which lubricates the curved surface of the journal 15 and the curved surface of the piston and also for conducting oil through the passage 309 for lubricating the bearings 216. The back bearings 220 are lubricated by an oil passage (not shown) similar to oil passage 303 that lubricates bearings 229. Thus, with the apparatus of this invention positive pressure lubrication may be provided to many of the bearing surfaces for lubricating the device during its operation.

It will be appreciated and understood that the various sealing systems illustrated in FIGS. 1-14 of the drawings may be used in the type of compressor illustrated in FIGS. 15-19. Similarly, the sealing system illustrated in this application may be used in other high pressure applications of the spherical displacement device other than compressors.

Another alternate embodiment of the present invention is shown in FIGS. 20 and 21 of the drawings wherein a spherical displacement device is provided in which one end piston is either formed integrally with or fixed against rotation in the spherical housing H. In this embodiment, the end piston P-2 is either formed integrally with or fixed against rotation relative to the chamber C in the housing H. Of course, in this fixed piston embodiment no seals are required between the piston P-2" and the surrounding housing; however,

strip seals and pin end seals are provided for sealing between the journal on the center piston P-3" and the fixed end piston P-2. The center piston P-3 is substantially identical to the center piston shown in the FIG. 1 embodiment.

As shown in FIGS. 20 and 21, the other end piston P-l" is shown rotatably mounted on a crank shaft 400 which is inclined relative to the axis P-1 and which is mounted eccentrically with respect to such axis on a rotating shaft 402 which is rotatably mounted so as to turn on the axis P-l. As shown in the drawings, such shaft 402 is mounted in suitable bearings 404.

As shown in FIG. 21 of the drawings, the inclined crank shaft 400 described a cone indicated by the number 406 as such inclined shaft rotates through the circle 407 around the axis P-l.

Rotation of the shaft 402 in a clockwise direction as viewed from the right hand end of FIG. 20 of the drawings causes the center piston P-3" to oscillate back and forth between the fixed end piston P-2 and the nutating piston P-1 and further, such rotation of the shaft 402 causes the inclined or crank shaft 400 to rotate in the opening in the piston P-l so as to cause reciprocal motion between the end piston P-1" and the center P- 2".

Thus, it will be appreciated, that the effect of the relative motion between the fixed end piston P-2' the oscillating center P-3" and the nutating end piston P-l" will be substantially the same as the effect of the relative motion between the pistons P-1, P-2 and P-2 shown in the FIG. 1 embodiment, i.e., positive displacement of fluid in the respective chambers formed between such pistons will be effected. Further, it will also be appreciated that the seal means used for sealing the pistons P-l and P-2" with respect to each other and with respect to the surrounding housing as well as with respect to the end piston P-2" will be substantially identical as the seal means illustrated in conjunction with the other embodiments shown herein. Further, fluid flow through inlet and discharge ports for each chamber formed between adjacent piston faces is controlled by check valves 410. v

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape, and materials'as well as in the details of the illustrated construction may be made without departing from the spirit of the invention.

What is claimed is:

1. In a spherical displacement device having a plurality of variable volume chambers for use as a pump, compressor or motor comprising a housing having a cavity therein, at least a portion of which has a substantially spherical configuration, a pair of end pistons disposed in said spherical cavity, each of said end pistons being mounted for rotation in said spherical cavity about an axis of rotation, the axis of rotation of each of said pair of end pistons being disposed at an angle other than with respect to the other axis of rotation, each of said pair of end pistons having a pair of faces inclined axially inwardly toward the center of said spherical cavity, first semi-cylindrical journal means in each of said pair of pistons extending diametrically of said spherical cavity, a central piston disposed in said spherical cavity between said pair of end pistons and extending diametrically of said spherical chamber, said central piston having a second semi-cylindrical journal means on opposite sides thereof for operably connecting said first semi-cylindrical journal means of each of said pair of end pistons and a pair of piston faces on each side of said second journal means aligned with said inclined piston surfaces to form a plurality of chambers in said spherical cavity whereby said central piston is simultaneously oscillated as it rotates with said pairs of pistons to vary the volume of said plurality of chambers, an improved sealing arrangement for sealing between said end pistons, said central piston and said spherical housing comprising:

a. semi-cylindrical end seal members on opposite ends of the semi-cylindrical journal means on said central piston and positioned externally of said semi-cylindrical journal with the ends of said semicylindrical end seals received in slots in said center pistons adjacent said semi-cylindrical journal means; and

b. arcuate ring seal segments disposed in grooves extending circumferentially of said center piston be- I tween said semi-cylindrical end seal members.

2. The invention of claim 1 wherein said arcuate ring segment seals have tapered ends adjacent said semicylindrical end seal members and including wedgeshaped lock means positioned between said tapered ends of said arcuate ring seal segments and said semicylindrical end seal members for limiting longitudinal movement of said arcuate ring seal segments in their grooves'upon rotation of said center piston in said spherical chamber and for sealing between said semicylindrical end seal members and said tapered end segments adjacent thereto to prevent leakage of pressure from behind said arcuate ring seal segments.

3. The invention of claim 1 including plug seal means provided at the juncture of said semi-cylindrical end seal members and said arcuate ring seal segments with slot means provided in said plug means for receiving said arcuate ring segment seals with said center piston being provided with suitable openings for receiving said plug seal means whereby high pressure gas in said circumferentially extending grooves is prevented from leaking around said center piston.

4. The invention of claim 3 including fluid passage means in said end piston for communicating high pressure fluid to the opening in said end piston in which said plug means is received for urging said plug means outwardly into said sealing engagement with said arcuate ring segment seal.

5. The invention of claim 3 wherein spring means are provided in said openings in said center piston for urging said plug seal means radially outwardly.

6. The invention of claim 5 wherein said plug seal means includes a hollow tubular member having a notch formed in its outer end for receiving said ring seal means and having a movable piston disposed in said hollow tubular member adapted to engage the inner surface of said ring seal means and having spring means for urging said piston means and said tubular member radially outwardly into sealing engagement with said ring seal means.

7. In a spherical displacement device having a plurality of variable volume chambers for use as a pump, compressor or motor comprising a housing having a cavity therein, at least a portion of which has a substantially spherical configuration, a pair of end pistons disposed in said spherical cavity, each of said end pistons being mounted for rotation in said spherical cavity about an axis of rotation, the axis of rotation of each of said pair of end pistons being disposed at an angle other than with respect to the other axis of rotation, each of said pair of end pistons having a pair of faces inclined axially inwardly toward the center of said spherical cavity, first semi-cylindrical journal means in each of said pair of pistons extending diametrically of said spherical cavity, a central piston disposed in said spherical cavity between said pair of end pistons and extending diametrically of said spherical chamber, said central piston having a second semi-cylindrical journal means on opposite sides thereof for operably connecting said first semi-cylindrical journal means of each of said pair of end pistons and a pair of piston faces on each side of said second journal means aligned with said inclined piston surfaces to form a plurality of chambers in said spherical cavity whereby said central piston is simultaneously oscillated as it rotates with said pairs of pistons to vary the volume of said plurality of chambers, an improved sealing arrangement for sealing between said end pistons, said central piston and said spherical housing comprising:

arcuate ring segment seals disposed in grooves in said end pistons with the ends of said arcuate ring segment seals tapered to a point and strip seal means extending axially of said semi-cylindrical journal means in each of said end pistons with the ends of said strip seal means being tapered to interfit with the tapered ends of said arcuate ring segment seals and with spring means for urging said tapered ends of said strip seal means into engagement with said tapered ends of said arcuate ring segment seals.

8. The invention of claim 7 wherein said arcuate ring segment seals are disposed in grooves substantially parallel to the inclined faces of said end pistons.

9. The invention of claim 7 wherein said arcuate ring segment seal is disposed in a continuous groove extending circumferentially of said end piston and in a plane which is not perpendicular to the axis of rotation of said piston.

10. The invention of claim 7 including side seal means which are disposed in grooves substantially perpendicular to said arcuate ring segment seals with wedge-shaped seal means disposed between the ends of said arcuate ring segment seals and said side seal means.

11. The invention of claim 7 wherein said side seal means are provided with wedge-shaped seal means adjacent the first semi-cylindrical journal means on said central piston for engaging the semi-cylindrical end seal members on the semi-cylindrical journal means on said central piston.

12. The invention of claim 11 including spring means for urging said wedge-shaped seal means outwardly between said side seal members and the adjacent semicylindrical end seal member on said semi-cylindrical journal means on the central piston. 

1. In a spherical displacement device having a plurality of variable volume chambers for use as a pump, compressor or motor comprising a housing having a cavity therein, at least a portion of which has a substantially spherical configuration, a pair of end pistons disposed in said spherical cavity, each of said end pistons being mounted for rotation in said spherical cavity about an axis of rotation, the axis of rotation of each of said pair of end pistons being disposed at an angle other than 180* with respect to the other axis of rotation, each of said pair of end pistons having a pair of faces inclined axially inwardly toward the center of said spherical cavity, first semi-cylindrical journal means in each of said pair of pistons extending diametrically of said spherical cavity, a central piston disposed in said spherical cavity between said pair of end pistons and extending diametrically of said spherical chamber, said central piston having a second semi-cylindrical journal means on opposite sides thereof for operably connecting said first semi-cylindrical journal means of each of said pair of end pistons and a pair of piston faces on each side of said second journal means aligned with said inclined piston surfaces to form a plurality of chambers in said spherical cavity whereby said central piston is simultaneously oScillated as it rotates with said pairs of pistons to vary the volume of said plurality of chambers, an improved sealing arrangement for sealing between said end pistons, said central piston and said spherical housing comprising: a. semi-cylindrical end seal members on opposite ends of the semi-cylindrical journal means on said central piston and positioned externally of said semi-cylindrical journal with the ends of said semi-cylindrical end seals received in slots in said center pistons adjacent said semi-cylindrical journal means; and b. arcuate ring seal segments disposed in grooves extending circumferentially of said center piston between said semicylindrical end seal members.
 2. The invention of claim 1 wherein said arcuate ring segment seals have tapered ends adjacent said semi-cylindrical end seal members and including wedge-shaped lock means positioned between said tapered ends of said arcuate ring seal segments and said semi-cylindrical end seal members for limiting longitudinal movement of said arcuate ring seal segments in their grooves upon rotation of said center piston in said spherical chamber and for sealing between said semi-cylindrical end seal members and said tapered end segments adjacent thereto to prevent leakage of pressure from behind said arcuate ring seal segments.
 3. The invention of claim 1 including plug seal means provided at the juncture of said semi-cylindrical end seal members and said arcuate ring seal segments with slot means provided in said plug means for receiving said arcuate ring segment seals with said center piston being provided with suitable openings for receiving said plug seal means whereby high pressure gas in said circumferentially extending grooves is prevented from leaking around said center piston.
 4. The invention of claim 3 including fluid passage means in said end piston for communicating high pressure fluid to the opening in said end piston in which said plug means is received for urging said plug means outwardly into said sealing engagement with said arcuate ring segment seal.
 5. The invention of claim 3 wherein spring means are provided in said openings in said center piston for urging said plug seal means radially outwardly.
 6. The invention of claim 5 wherein said plug seal means includes a hollow tubular member having a notch formed in its outer end for receiving said ring seal means and having a movable piston disposed in said hollow tubular member adapted to engage the inner surface of said ring seal means and having spring means for urging said piston means and said tubular member radially outwardly into sealing engagement with said ring seal means.
 7. In a spherical displacement device having a plurality of variable volume chambers for use as a pump, compressor or motor comprising a housing having a cavity therein, at least a portion of which has a substantially spherical configuration, a pair of end pistons disposed in said spherical cavity, each of said end pistons being mounted for rotation in said spherical cavity about an axis of rotation, the axis of rotation of each of said pair of end pistons being disposed at an angle other than 180* with respect to the other axis of rotation, each of said pair of end pistons having a pair of faces inclined axially inwardly toward the center of said spherical cavity, first semi-cylindrical journal means in each of said pair of pistons extending diametrically of said spherical cavity, a central piston disposed in said spherical cavity between said pair of end pistons and extending diametrically of said spherical chamber, said central piston having a second semi-cylindrical journal means on opposite sides thereof for operably connecting said first semi-cylindrical journal means of each of said pair of end pistons and a pair of piston faces on each side of said second journal means aligned with said inclined piston surfaces to form a plurality of chambers in said spherical cavity whereby said central piston is simultaneously oscillaTed as it rotates with said pairs of pistons to vary the volume of said plurality of chambers, an improved sealing arrangement for sealing between said end pistons, said central piston and said spherical housing comprising: arcuate ring segment seals disposed in grooves in said end pistons with the ends of said arcuate ring segment seals tapered to a point and strip seal means extending axially of said semi-cylindrical journal means in each of said end pistons with the ends of said strip seal means being tapered to interfit with the tapered ends of said arcuate ring segment seals and with spring means for urging said tapered ends of said strip seal means into engagement with said tapered ends of said arcuate ring segment seals.
 8. The invention of claim 7 wherein said arcuate ring segment seals are disposed in grooves substantially parallel to the inclined faces of said end pistons.
 9. The invention of claim 7 wherein said arcuate ring segment seal is disposed in a continuous groove extending circumferentially of said end piston and in a plane which is not perpendicular to the axis of rotation of said piston.
 10. The invention of claim 7 including side seal means which are disposed in grooves substantially perpendicular to said arcuate ring segment seals with wedge-shaped seal means disposed between the ends of said arcuate ring segment seals and said side seal means.
 11. The invention of claim 7 wherein said side seal means are provided with wedge-shaped seal means adjacent the first semi-cylindrical journal means on said central piston for engaging the semi-cylindrical end seal members on the semi-cylindrical journal means on said central piston.
 12. The invention of claim 11 including spring means for urging said wedge-shaped seal means outwardly between said side seal members and the adjacent semi-cylindrical end seal member on said semi-cylindrical journal means on the central piston. 